test-integration_skill

Overview

This skill helps you design and produce integration tests that verify interactions across component boundaries, APIs, databases, and end-to-end flows. It provides a focused checklist and a prioritized reporting format to turn architectural concerns into concrete test plans. Use it to ensure components collaborate correctly and high-value cross-system paths are covered.

How this skill works

I inspect component interaction patterns, API contracts, database transaction behavior, and full data flows to generate targeted integration tests. For each area I produce test cases that exercise real interfaces, validate contracts and transactional guarantees, and trace data through all processing layers. I also assign priority ratings (Must/Should/Could/Won't) so you know which tests to implement first.

When to use it

• When multiple modules must communicate through real interfaces rather than mocks
• When verifying API contract compliance, status codes, headers, pagination, or versioning
• When changes touch database schema, migrations, transactions, or cascading behavior
• When validating end-to-end user workflows that traverse services and layers
• When adding or refactoring dependency injection, event wiring, or lifecycle management

Best practices

• Prefer real interfaces and lightweight test doubles only for external third parties
• Start with Must-paths that guarantee system correctness before adding Should/Could scenarios
• Keep tests deterministic: seed data, isolate transactions, and clean up resources after each run
• Validate API contracts with both happy paths and representative error cases, including headers and status codes
• Test transactions for rollback and concurrent access; include migration verification in CI

Example use cases

• Verify that a service call triggers database updates and pub/sub events in the correct order (Must)
• Confirm API endpoints preserve response shape, headers, and pagination after a version bump (Should)
• Test that failed operations correctly roll back transactions and leave no partial state (Must)
• Trace a full user checkout flow across frontend, order service, payment gateway mock, and inventory updates (Must)
• Add edge-case scenarios for rate limits, sorting/filtering combinations, and unusual header combinations (Could)